CHAPTER 18- PLASTICS, SKIN, AND SOFT TISSUES.txt

Keratinocytes- main cell type in epidermis; originates from basal layer; provide mechanical barrier

• Melanocytes- neuroectodermal origin (neural crest cells); in basal layer of epidermis
• - have dendritic processes that transfer melanin to neighboring keratinocytes via melanosomes
• - density of melanocytes is the same among races; difference is in production

primarily structural proteins for the epidermis

• 1) act as antigen-presenting cells (MHC class II)
• 2) originate from bone marrow
• 3) have a role in contact hypersensitivity reactions (type IV)

• 1) pacinian corpuscles- pressure
• 2) ruffini's endings- warmth
• 3) krause's end-bulbs- cold
• 4) meissner's corpuscles- tactile sense

aqueous sweat (thermal regulation, usually hypotonic)

• 1) milky sweat
• 2) highest concentration of glands in palms, and soles
• 3) most sweat is the result of sympathetic nervous system via acetylcholine

lipid soluble drugs

• 1) predominant type
• 2) 70% of weight of dermis
• 3) gives tensile strength

resistance to stretching (collagen)

ability to regain shape (branching proteins that can stretch to 2x)

caused by loss of tensile strength and elasticity

• 1) include all of the epidermis and part of the dermis
• 2) donor site skin regenerated from hair follicles and skin edges on split-thickness grafts
• 3) STSGs- are more likely to survive --> graft not as thick so easier for imbibition and subsequent revascularization to occur

have less wound contraction--> good for areas such as the palms and back of hands

blood supply to skin graft for days 0-3

• 1) starts around day #3
• 2) poor vascularized beds are unlikely to support skin grafting -->
• - tendon
• - bone without periosteum
• - XRT areas

venous thrombosis

• Tissue expansion occurs by:
• 1) local recruitement
• 2) thinning of the dermis + epidermis
• 3) mitosis

• 1) rely on superior epigastric vessels
• 2) periumbilical perforators are the most important determinant of TRAM flap viability
• 3) complications:
• 1- flap necrosis
• 2- ventral hernia
• 3- bleeding
• 4- infection
• 5- abdominal wall weakness

• Stage I:
• Erythema and pain, no skin loss

• Stage II:
• Partial skin loss with yellow debris
• Tx: local treatment, keep pressure off

• Stage III:
• Full-thickness skin loss, subcutaneous tissue exposure
• Tx: sharp debridement; will likely need myocutaneous flap

• Stage IV:
• Usually involves bony cortex
• Tx: myocutaneous flaps

• 1) damages DNA and repair mechanisms
• 2) both promotor and initiator
• 3) melanin single best factor for protecting skin from UV radiation
• 4) UV-B: responsible for chronic sun damage

1) represents only 3-5% of skin Ca but accounts for 65% of deaths

• 1) dysplastic, atypical or large, or large congenital nevi- 10% lifetime risk for melanoma
• 2) familial BK mole syndrome- almost 100% risk of melanoma
• 3) xeroderma pigmentosum
• 4) fair complexion, easy sunburn, intermittent sunburns, previous skin Ca, previous XRT

10%

• 1) back in men
• 2) legs in women

• 1) men
• 2) ulcerated lesions
• 3) ocular and mucosal lesions

• 1) color change
• 2) angulations
• 3) indentation/notching
• 4) englargement
• 5) darkening
• 6) bleeding
• 7) ulceration

originates from neural crest cells (melanocytes) in basal layer epidermis

blue color

lung

melanoma

1) <2 cm lesion- excisional biopsy (tru-cut core needle biopsy) unless cosmetically sensitive area- need resection w/margins if pathology comes back as melanoma

2) >2cm lesions or cosmetically sensitive area- incisional biopsy (or punch biopsy), will need to resect w/margins if pathology shows melanoma

• Lentigo maligna:
• 1) least aggressive
• 2) minimal invasion
• 3) radial growth 1st usually
• 4) elevated nodules

• Superficial spreading melanoma:
• 1) most common
• 2) intermediate malignancy
• 3) originates from nevus/sun-exposed areas

• Nodular:
• 1) most aggressive
• 2) mostly likely to have metastasized at time of diagnosis
• 3) deepest growth at time of diagnosis
• 4) vertical growth first
• 5) bluish/black with smooth borders
• 6) occurs anywhere in the body

• Acral lentiginous:
• 1) very aggresive
• 2) palms/soles of african americans

0.5cm margins are OK

• 1) need CXR and LFTs
• 2) examine all possible draining lymph nodes

resection of primary tumor with appropriate margins

• 1) alpha-interferon
• 2) IL-2
• 3) tumor vaccines

• 1) always need to resect clinically positive nodes with melanoma
• 2) perform sentinel lymph node biopsy if nodes clinically negative and tumor >1mm deep
• 3) involved nodes usually nontender, round, hard, 1-2 cm
• 4) all stage III tumors need full lymph node dissection
• 5) need to include superficial parotidectomy for anterior head and neck melanomas

complete axillary node dissection

1) Resection of metastases has provided some patients with long disease-free interval and is the best chance for cure.

2) Isolated metastases (i.e. lung or liver) that can be resected with a low risk procedure should probably undergo resection

• Primary Tumor
• Tx: cannot be assessed (shaved biopsy, regressed lesion)
• T0: unknown primary
• Tis: in situ melanoma
• T1: 1.0 mm Breslow thickness
• a) without ulceration
• b) with ulceration or clark level IV or V
• T2: 1.01-2.0 mm
• a) without ulceration
• b) with ulceration
• T3: 2.01-4.0 mm
• a) without ulceration
• b) with ulceration
• T4: >4mm
• a) without ulceration
• b) with ulceration

• Regional Lymph Node Involvement
• Nx: cannot be assessed (previously removed)
• N0: no regional node metastasis
• N1: Metastasis to one regional node
• a) micrometastasis (diagnosed by SLNB or elective node dissection)
• b) macrometastasis (clinically palpable or found on imaging studies, confirmed histologically, or gross extracapsular extension)
• N2: metastasis in two or three regional nodes
• a) micrometastasis
• b) macrometastasis
• c) in-transit or satellite metastasis without nodal metastasis
• N3: metastasis 4 regional nodes, matted nodes, or in-transit or satellite metastasis with positive metastatic nodes

• Distant Metastasis
• Mx: cannot be assessed
• M0- no distant metastasis
• M1a: distant skin, subcutaneous, or lymph node metastasis with normal LDH
• M1b: lung metastasis with normal LDH
• M1c: all other distant metastasis or any distant site with elevated LDH

• I- epidermis basement membrane intact
• II- papillary dermis through basement membrane
• III- juncitonal dermis between papillary and reticular dermis
• IV- reticular dermis
• V- fat

• <1mm depth: 1cm margin
• 1-4mm depth: need 2cm margin
• >4mm depth: need 2-3cm margin

• 1) basal cell carcinoma
• 2) it is 4x more common than squamous cell carcinoma

80% are on the head and neck

originates from epidermis- basal epithelial cells and hair follicles

pearly appearance, rolled borders

peripheral palisading of nuclei and stromal retraction

• 1) slow indolent growth
• 2) ulcerative, rare metastases, deep invasion, occasionally dark

regional adenectomy

• 1) most aggressive
• 2) has collagenase production

• 1) 0.3-0.5cm margins
• 2) XRT and chemotherapy- may be of limited benefit for inoperable disease or metastases; neuro, lymphatic, or vessel invasion

• 1) overlying erythema, papulonodual with crust and ulceration
• 2) may have surrounding induration and satellite nodules
• 3) usually red/brown; can have a pearly appearance

1) metastasizes more frequently than basal cell ca but less commonly than melanoma

• 1) actinic keratosis
• 2) xeroderma pigmentosum
• 3) bowen's disease
• 4) atrophic epidermis
• 5) arsenics
• 6) hydrocarbons (coal tar)
• 7) cholorophenols
• 8) nitrates
• 9) HPV
• 10) immunosuppression
• 11) sun exposure
• 12) fair skin
• 13) XRT exposure
• 14) previous skin Ca
• 15) can develop in old burn scars

• 1) poorly differentiated
• 2) greater depth
• 3) recurrent lesions
• 4) immunosuppression

• 1) 0.5-1cm margins for low risk
• 2) can treat high risk with MOHS surgery (margin mapping using conservative slices; not used for melanoma) when trying to minimize area of resection (i.e. lesions on face)
• 3) regional adenectomy for clinically positive nodes
• 4) XRT and chemotherapy- may be of limited benefit for inoperable disease or metastases; neuro, lymphatic or vessel invasion.

• #1- malignant fibrous histiosarcoma
• #2- liposarcoma

• 1) most sarcomas are large, grow rapidly, and are painless
• 2)50% arise from extremities, 50% in children (arise from embryonic mesoderm)

• 1) asymptomatic mass (most common presentation)
• 2) GI bleeding
• 3) bowel obstruction
• 4) neurologic deficit

• CXR: to r/o lung mets
• MRI before biopsy to r/o vascular, neuro, or bone invasion

• 1) excisional biopsy if mass <4cm
• 2) longitudinal incisional biopsy for masses >4cm (may need to eventually resect biopsy skin site if biopsy shows sarcoma

• 1) hematogenous spread, not to lymphatics--> metastasis to nodes is rare
• 2) Lung is the most common site of metastasis

staging based on grade, not size or nodes

• 1) want at least 3cm margins and at least 1 uninvolved fascial plane--> try to perform limb sparing operation
• 2) place clips to mark site of likely recurrence --> will XRT these later
• 3) postop XRT- for high-grade tumors, close margins, or tumors >5cm
• 4) chemotherapy is doxorubicin based
• 5) tumors >10cm may benefit from preop XRT and chemotherapy- may allow limb sparing resection
• 6) Isolated sarcoma metastases without other evidence of systemic disease (i.e. lung or liver) can be resected and are the best chance for survival; otherwise can palliate with XRT
• 7) midline incision favored for pelvic and retroperitoneal sarcomas
• 8) with resection, try to preserve motor nerve and retain or reconstruct vessels

• 1) prognosis is poor overall
• 2) delay in diagnosis
• 3) difficulty with total resection
• 4) difficulty getting XRT to pelvic tumors
• 5) 40% 5 year survival rate with complete resection

• 1) can occur in the pediatric population (usually rhabdomyosarcoma)
• 2) hard to get margin because of proximity to vital structures
• 3) posop XRT for positive or close margins as negative margins may be impossible to obtain

• 1) most common are leiomyosarcomas and liposarcomas
• 2) ability to completely remove the tumor is the most important prognostic factor in visceral and retroperitoneal sarcomas

• asbestos: mesothelioma
• PVC and arsenic: angiosarcoma
• Other risk factors: XRT, chlorophenols, pesticides
• Chronic lymphedema: lymphangiosarcoma

• 1) vascular sarcoma
• 2) can involve skin, mucous membranes, or GI tract
• 3) associated with immunocompromised state
• 4) rarely a cause of death in AIDS; 15-20 year survival; slow growing
• 5) Treatment: XRT or intralesional vinblastine for local disease; systemic chemotherapy for disseminated disease
• 6) surgery for intestinal hemorrhage

• 1) #1 soft tissue sarcoma in kids
• 2) head/neck, genitourinary, extremeties + trunk (poorest prognosis)
• 3) embryonal subtype- most common
• 4) alveolar subtype- worst prognosis
• 5) Tx: surgery, doxorubicin-based chemotherapy

• 1) most are metastatic at the time of diagnosis
• 2) Osteosarcoma:
• 1- increased incidence around the knee
• 2- originates from metaphyseal cells
• 3- usually in children
• 3) usually need to take the joint, followed by reconstruction; may require amputation

• 1) CNS tumors
• 2) peripheral sheath tumors
• 3) pheochromocytoma

1) childhood rhabdomyosarcoma, many others

also include other sarcoma

angiomyolipoma

• 1) familial adenomatous polyposis
• 2) intraabdominal desmoids

• 1) yellow
• 2) contains histiocytes
• 3) Tx: excision

• 1) verruca vulgaris
• 2) viral origin
• 3) contagious
• 4) autoinoculable
• 5) can be painful
• 6) liquid nitrogen initially

• 1) common but rarely malignant
• 2) back, neck, between shoulders

• 1) can be associated with neurofibromatosis and von Recklinghausen's disease
• 2) cafe-au-lait spots, axillary freckling, optic nerve gliomas, CNS tumors

• Actinic keratosis-
• 1) premalignant
• 2) in sun-damaged areas
• 3) need excisional biopsy if suspicious

• Seborrheic keratosis
• 1) not premalignant
• 2) trunk on elderly
• 3) can be dark

Arsenical keratosis- associated with squamous cell carcinoma

• 1) are neuroendocrine
• 2) aggressive regional and systemic spread
• 3) patients have red to purple papulonodule/indurated plaque
• 4) have:
• 1- neuron-specific enolase (NSE)
• 2- cytokeratin
• 3- neurofilament protein

• 1) painful tumor composed of blood vessels and nerves
• 2) benign; most common in the terminal aspect of the digit
• 3) tx: tumor excision

• 1) in elderly
• 2) often on face
• 3) premalignant, not aggressive

important to line up vermillion border

• 1) usually benign
• 2) occur in fascial planes
• 3) Anterior abdominal wall (most common location) desmoids can occur during or following pregnancy; can also occur after trauma or surgery
• 4) Intra-abdominal desmoids associated with gardner's syndrome and retroperitoneal fibrosis
• 5) high risk of local recurrences, not distant spread
• 6) Tx: surgery or chemotherapy/XRT if vital structure involved

• 1) squamous cell carcinoma in situ
• 2) 10% turn into invasive squamous cell carcinoma
• 3) Tx: excision with negative margins usual (exception includes peri-anal region)

• 1) rapid growth, rolled edges, crater filled with keratin
• 2) is not malignant but can be confused with squamous cell carcinoma
• 3) involutes spontaneously over months
• 4) always biopsy these to be sure
• 5) if small, excise; if large, biopsy and observe

• 1) increased sweating
• 2) especially noticeable in the palms
• 3) sympathectomy if refractory

• 1) infection of the apocrine sweat glands
• 2) usually in the axilla and groin regions
• 3) staph/strep is most common organism
• 4) antibiotics, improved hygiene 1st; may need surgery

• 1) most common benign cyst
• 2) have completely mature epidermis with creamy keratin material

• 1) in scalp
• 2) no epidermis

• 1) over tendons
• 2) usually over wrist
• 3) filled with collagenous material

• 1) midline abdominal and sacral lesions
• 2) occiput and nose
• 3) found along body fusion planes

• 1) congenital coccygeal sinus with ingrown hair
• 2) gets infected and needs to be excised

• 1) autosomal dominant; dark skin
• 2) collagen goes beyond original scar
• 3) XRT, steroids, silicone, pressure garments

• 1) dark skin
• 2) flexor surfaces of upper torso
• 3) collagen stays within confines of scar
• 4) often occurs in burns or wounds that take a long time to heal
• 5) steroids, silicone, pressure garments